A Tale of Tails
The gentle rays of light submit to the pervasive encroachment of the clouds. The sky raises its fangs and hurls forth a blast from above, complete with a showering torrent and punishing stones.
At last the fury begins to subside, as a tranquil calm sets in over the area.
Something doesn’t feel right. The air begins to move in strange directions, as if it’s not sure where to go. Then the wind locks on to its next destination and slowly flows past. A rumble on the horizon is audible, but it’s not thunder, and it certainly is not a train. The untamed wind now whips toward the twisted mass of debris.
“RUN!” a voice says, “Don’t look back, just move! move! move!” A secure hiding place is found. “FLEE!” the voice exclaims. Almost all the surroundings are sucked into the void from above and purged a distance away from the twister’s dance.
Silence returns in earnest. Escape is the best option.
The Devil is in the Details
What Defines a Tornado?A tornado is generally defined as a violently rotating column of air that extends from a convective (puffy-looking) cloud to the surface of the ground, often times with visible debris at the surface. The rotating air column (vortex) must be completely connected to the cloud above it for it to be considered a tornado. It is important to note that this vortex of air spins in a relatively isolated location, while traveling along its path of movement.
Typically, most tornadoes reach a maximum diameter less than 11/4 miles (2 kilometers). However, there are some exceptions to the rules. The widest tornado ever recorded in history was the El Reno, Oklahoma twister which occurred on May 31, 2013. The El Reno tornado had a maximum width of 2.6 miles and produced winds that were measured near 300 miles per hour, ranking it among the top intense tornados ever documented. The below image depicts the outlined width of the tornado as it traveled along its path.
The gentle rays of light submit to the pervasive encroachment of the clouds. The sky raises its fangs and hurls forth a blast from above, complete with a showering torrent and punishing stones.
At last the fury begins to subside, as a tranquil calm sets in over the area.
Something doesn’t feel right. The air begins to move in strange directions, as if it’s not sure where to go. Then the wind locks on to its next destination and slowly flows past. A rumble on the horizon is audible, but it’s not thunder, and it certainly is not a train. The untamed wind now whips toward the twisted mass of debris.
“RUN!” a voice says, “Don’t look back, just move! move! move!” A secure hiding place is found. “FLEE!” the voice exclaims. Almost all the surroundings are sucked into the void from above and purged a distance away from the twister’s dance.
Silence returns in earnest. Escape is the best option.
The Devil is in the Details
What Defines a Tornado?A tornado is generally defined as a violently rotating column of air that extends from a convective (puffy-looking) cloud to the surface of the ground, often times with visible debris at the surface. The rotating air column (vortex) must be completely connected to the cloud above it for it to be considered a tornado. It is important to note that this vortex of air spins in a relatively isolated location, while traveling along its path of movement.
Typically, most tornadoes reach a maximum diameter less than 11/4 miles (2 kilometers). However, there are some exceptions to the rules. The widest tornado ever recorded in history was the El Reno, Oklahoma twister which occurred on May 31, 2013. The El Reno tornado had a maximum width of 2.6 miles and produced winds that were measured near 300 miles per hour, ranking it among the top intense tornados ever documented. The below image depicts the outlined width of the tornado as it traveled along its path.
How do Tornadoes Form? Tornadoes usually require a thunderstorm environment to develop. Thunderstorms need several main ingredients in order to form: moisture, instability (buoyancy of air) and upward motion. In a situation supportive of the development of tornadoes, a significant change in wind direction and/or speed between the ground level wind and the higher layers in Earth’s atmosphere is a key factor for determining whether tornadoes are likely to form. This difference in the vertical wind profile of the atmosphere is known as vertical wind shear.
The presence of strong vertical wind sheer creates a series of horizontal, cylindrically-shaped eddies in the sky – invisible to the naked eye without the presence of clouds, dust, etc. These rolling eddies pose no threat and commonly occur in many different atmospheric weather conditions. What is different in this case, is that warm pockets of air are able to rise from the ground (updrafts of air) and latch on to the horizontal rolling nature of of the eddy. If the updraft rises with enough force, the quickly ascending air causes the horizontally spinning air to bulge upward into a the shape of a horseshoe or an upside-down ‘U’ pattern in contact with the ground. The formation of tornadoes is most likely in the region of a thunderstorm where the tilted rotating air intersects the updraft near the surface of the ground. The following chronological diagram illustrates the creation of tornadoes.
It is possible to make a ‘miniature tornado’ or a relatively fast spinning vortex in the comfort of your home; rest assured you will not be threatened by the vortex in this experiment. First, bring a pot of water to a boil, releasing plenty of steam from the surface of the water. The presence of the steam is very important for the demonstration to work properly. Once the steam is visibly rising above the water, cup your hand so that the palm of your hand faces a horizontal direction. Then swipe your hand from one side of the pot to the other, about four inches above the water. You may need to adjust the height and speed if you are not able to get a mini vortex to form. It may also work to lightly blow at the surface of the water, while using your hand to create a stronger wind above the pot in a slightly different direction than the surface wind.
Where do Tornadoes Form? Tornadoes form in many geographic regions across the planet. The United States experiences more tornadoes annually than any other country on Earth. As you can see from the following map, the highest concentration of tornadoes in the United State is generally located over the southern Great Plains region.
Where do Tornadoes Form? Tornadoes form in many geographic regions across the planet. The United States experiences more tornadoes annually than any other country on Earth. As you can see from the following map, the highest concentration of tornadoes in the United State is generally located over the southern Great Plains region.
You may have heard or read about a substantial increase in tornado occurrence in recent years. While a very noticeable fluctuation in the annual number of tornadoes can occur over a period of several years, a longer term (several decades to centuries) trend can not yet be accurately established. The underlying reasons for this are related to a substantial increase in public awareness and reporting of severe weather events, as well as population growth within the past several decades. Below, I posted a chart which shows the tornado counts and reports in the continental United States.
To wrap up this post, here is a short explanation of tornado development by a Tennessee TV weather anchor named Ken Weathers: